User guide

14797 • November 2004 • Making Connections to the Frame
Page 14
Alarm Connections
The ALARMS connector includes normally closed connections from pin 1 and pin 2 to
COM, which is connected to chassis ground. If both Power Supply modules fail (or AC
is disconnected from both), the pin 1 to COM circuit opens. The alarm associated with
pin 2 is reserved for future use.
Figure 10 shows one circuit that can be used with the Alarms connector. It contains
LEDs that are normally OFF and turn ON to indicate a failure.
Figure 10. Alarm Connections
Caution: The power supply for the alarm circuit must not exceed 30 VDC or 150 mA.
Load resistor value varies depending on voltage.
NC
NC
2
COM
1 P/S fail
S5000 Internal
S5000
Rear Alarm
Connector
Example Circuit
LEDs switch ON to indicate fault
470
470
22k
1k
22k
1k
Q1
Q2
LED1
LED2
9 - 18 VDC
+
_
1 C OM 2
Alarms
see text